1. Field of the Invention
The present invention generally relates to digital communications, and more particularly, to an apparatus for decoding encoded voice signal.
This application is a counterpart of Japanese patent application, Serial Number 32588/2001, filed Feb. 8, 2001, the subject matter of which is incorporated herein by reference.
2. Description of the Related Art
Pulse code modulation (PCM) code is one of the codes which modulate an analog voice signal to a digital data. PCM code is sampled the analog voice signal every a certain timing as a digital data and is stored one. The quality of the digital data depends on the number of sampling per second (sampling frequency) and the number of bits of the data (sample quantizing level). For example, the standard systems, the Cordless Telephone II(CT2), specify sampling at 8 kHz and quantizing to 15 levels. Adaptive differential pulse code modulation (ADPCM)